Here's a comment that I've just posted to that site. It's "awaiting moderation". I don't expect it to appear (none of the occasional ones sent these last 5 years have done so).
Evidence for authenticity "overwhelming"? Nothing could be further from the truth. The evidence in fact is paltry and usually circumstantial, and even then, inconsistent and fragmentary.
The radiocarbon date coincides with the first appearance of the TWO-FOLD, HEAD-To-HEAD image seen on the Lirey badge, whose date is self-evident from the De Charny coats-of-arms. All that is missing is a coherent narrative for the history and motivation, and one that accounts for what otherwise might seem enigmatic features - but which aren't in reality, once one has torn oneself away from the authenticity narrative.
This investigator has supplied the missing narrative, based on 5 years research and the resulting 'Model 10'. i.e. flour imprinting/thermal development/final water-washing.
The motivation? To simulate what a body imprint in sweat and blood onto Joseph of Arimathea's fine linen might look like 13 centuries later, acquired during TRANSPORT from cross to tomb. The TS was intended to be a whole-body rival to the then-celebrated Veil of Veronica, while based on broadly the same principles of image-acquisition. The negative image, 3D properties etc are exactly what one would expect from a contact image obtained with white flour onto wet linen, as I have repeatedly demonstrated these last 18 months, using 3D figurines as well as my own hand and face.
"Overwhelming" evidence for authenticity you say, when there's a rival narrative that ticks far more boxes? How much longer are you prepared to blind yourself and others to the progress of science?